FCAW orbital pipe welding technology improves fab shop productivity
Fabricators, like all companies facing increasing competition, are reevaluating and redesigning work flow and plant layout, and implementing new techniques to improve productivity and reduce work-in-process times. Submerged arc welding (SAW) has been widely used for years to produce high-quality mechanized butt joint welds in pipe, but requires workpieces to be rotated under a fixed torch. Submerged arc welding can provide high deposition rates, but requires considerable capital expenditures for turning rolls and positioners, especially if the pipe work consists of larger-diameter pipe, long lengths and heavy assemblies. Spool pieces with complex or asymmetrical configurations (elbows, for example) often cannot be conveniently rotated without special and time-consuming fixturing. Many assemblies may consist of pipe connections that must be made in position. Traditionally, these welds have been made using manual techniques: shielded metal arc welding (SMAW), gas tungsten arc welding (GTAW) or a combination of processes by skilled welders. With the growing shortage of skilled welders worldwide, fabricators are increasingly evaluating different processes and techniques to compensate for less-skilled welders or to improve the productivity of their skilled work force. One technique increasingly being used in mechanized orbital flux cored arc welding (FCAW). FCAW might be thought of as the submerged arc process turned inside out. With SAW, a solid wire electrode is simultaneously fed into the weld pool along with powdered flux. Instead of solid wire, FCAW substitutes a metal tube or sheath, wrapped around a core of flux. The orbital systems on the market today use additional gas shielding of the weld pool. All-position FCAW wires are formulated with fluxing agents that promote rapid pool solidification, which allow welds to be made in all positions.
- Research Organization:
- Magnatech Ltd. Partnership, East Granby, CT (US)
- OSTI ID:
- 20005578
- Journal Information:
- Welding Journal (Miami), Vol. 78, Issue 11; Other Information: PBD: Nov 1999; ISSN 0043-2296
- Country of Publication:
- United States
- Language:
- English
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